Audi 100 AAT: Upgrade to A6 AAT Technology?

I've already used the search function, but unfortunately, the posts containing the necessary information were deleted at the user's request.

Okay, so I'll start from the very beginning:

I have:
An Audi 100 2.5 TDI AAT, manufactured in December 1993.

Okay, and now here's what I'm planning:
- Replace the fuel injection pump with an HDK pump from an Audi A6 2.5 TDI with engine code AAT.
- Replace the engine/control unit wiring harness with the one from the A6 AAT.
Connect the control unit (STG) using the Bosch part number (0 281 001 253/254) or the Audi part number (4A0 907 401 E).

Furthermore, I have a complete WFS (Wireless Flight System) available, and my retrofitted interior door locks also have transponders, and the ignition switch has a reading coil.

Meaning:
- I've wanted a cruise control system for a long time.
-The STG has an MTM chip.
-I'm getting the HDK pump (150,000 km) in exchange for mine (200,000 km).

So, now I would like to know if I have forgotten anything, or if anyone knows whether my plan is technically not possible.

Before I get started taking the pump out to replace it tomorrow.

Regards,

Joe Klugmann.

Hi,
Actually, almost everything is different with the A6. The injectors might be interesting here, but I'm not sure exactly what's different. Also, the turbocharger responds more quickly, and in conjunction with the chip, this could lead to increased soot production at lower RPMs – something to test.

So, the fuel injectors and the turbocharger have different part numbers on the A6 AAT.

'I just removed the ESP system, but there are people who run an A6 AAT engine with a 100-spec fuel pump and a 100-spec engine control unit (ECU), and that works, so it should work the other way around too.'

Well, practice makes perfect, but it would be stupid if I gave away my pump and then it doesn't work later.

I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.

#######################################
# Injector Nozzles A6:
# MKB: Target Value/New Wear Limit
# AAT, AEL 190...200 bar 170 bar
#######################################
# Data Injection Nozzles 100:
# MKB: Target Value/New Wear Limit
# AAT 190...200 bar 170 bar
#######################################

I took that information from my exam materials, and I don't think the turbocharger has been modified.

But maybe someone among you knows more about the differences.

Regards,

Joe.

Hi!

The injectors on the AEL open at 10-20 bar higher pressure, but those on the A6 AAT are the same. The only question would be the needle lift adjuster. I'm not entirely sure if that's identical. If you want to replace the wiring harness, you'll need a new instrument cluster (otherwise the ABS warning light will always be on), a new intake manifold pressure sensor, and different air filter housings (due to the EGR system). If I think about it more, I'm sure I could come up with a lot more things, but I don't think it would be as simple as you might imagine.

Hi!

The injectors on the AEL open at 10-20 bar higher pressure, but those on the A6 AAT are the same. The only question would be the needle lift adjuster. I'm not entirely sure if that's identical. If you want to replace the wiring harness, you'll need a new instrument cluster (otherwise the ABS warning light will always be on), a new intake manifold pressure sensor, and different air filter housings (due to the EGR system). If I think about it more, I'm sure I could come up with a lot more things, but I don't think it would be as simple as you might imagine.

Joe Klugmann wrote:

I don't think the turbo has been changed.

He is, though.

The AAT engine in the A6 has the same turbocharger as the AEL engine in the A6. It was modified, which is why the newer AAT engines have better responsiveness. That's my understanding.

The AAT in the A6 has the same turbocharger as the AEL in the A6. It was modified, which is why the newer AAT has better responsiveness. That's my information.

Okay, the Turoblader parts are the same; I had an A6 AAT and an A6 AEL here for comparison.
The change in responsiveness is probably related to the software.

I now also have all the necessary parts for the conversion, and I will start working on it next week.

However, I will not be replacing the engine wiring harness, but rather reconnecting it.

I just requested an expert opinion from MTM regarding the chip.

I think I will be able to tell you next week, probably towards the end, how it turned out and how he is behaving.

Regards,

Joe.